Pearson (2-1) tossed two scoreless innings of relief to earn the win in Saturday's 3-2 victory over the Blue Jays. He allowed one hit and two walks while striking out one.
The Blue Jays traded Pearson on Friday to the Cubs, Jesse Rogers of ESPN.com reports.
Pearson (illness) gave up an earned run on one hit and one walk over one inning out of the bullpen in Tuesday's 4-2 loss to the Rays.
Pearson is away from the team Saturday due to an illness, Mike Wilner of the Toronto Star reports.
Pearson notched his second save of the season Sunday against Cleveland, retiring the only batter he faced to preserve a 7-6 lead.
Pearson gave up a run on two hits while striking out one in an inning of relief Sunday to record his third hold of the season in an extra-inning win over the A's.
Pearson gave up two hits and struck out one in a scoreless ninth inning Monday to record his first save of the season in a win over the Royals.
The Blue Jays recalled Pearson from Triple-A Buffalo on Saturday, Shi Davidi of Sportsnet.ca reports.
Pearson was optioned to Triple-A Buffalo by the Blue Jays on Tuesday, Hazel Mae of Sportsnet reports.
Pearson struck out the side in a perfect ninth inning Sunday during a 5-0 win over the Rockies.